1. Technical Field
The present invention relates to a recording apparatus.
2. Related Art
As a type of a recording apparatus configured to record by attaching liquid (ink, for example) to a recording medium (printing sheet, for example), an ink jet printer (hereinafter, simply referred to as “printer”) configured to record predetermined images (including characters and figures) by ejecting ink onto a printing sheet from a recording unit (recording head, for example) is known. The printer is configured to record images on printing sheets by taking an uppermost printing sheet from a paper feed cassette (hereinafter, simply referred to as “cassette”) having a plurality of printing sheets placed in a stacked manner and feeding the same one by one toward the recording unit. Therefore, this printer is provided with a loading unit configured to unloadably accommodate the cassette having the plurality of printing sheets placed therein in a stacked manner by inserting and removing along the direction orthogonal to the stacking direction of the printing sheet, and a paper feed roller configured to take the printing sheets from the cassette in the state of being loaded in the loading unit one by one and feed the same in sequence toward the recording unit.
In this printer, formed at a position deep inside the loading unit in which the cassette is to be loaded, that is, at a portion to face an end surface of the cassette on the front side in the direction of insertion in a state of being loaded in the loading unit is a separating bevel configured to guide the printing sheets taken from the cassette by the paper feed roller and fed while being separated one by one to the recording unit. Therefore, if the speed of insertion of the cassette into the loading unit is fast when the cassette is loaded in the loading unit by a user, the printing sheets in the stacked state may move in the direction of insertion from the interior of the cassette and climb onto the separation bevel inclined upward due to an inertia force. In this case, the printing sheets cannot be separated one by one by the separation bevel and, consequently, a transporting state referred to as multi feed, in which a plurality of printing sheets are fed in a stacked state, may occur, which may lead to a problem such as paper jam.
As means for avoiding such a problem, JP-A-2000-335769 discloses a configuration having a shutter member which moves downward from an upper retracted position to a lower restricting position for restricting downstream ends of the printing sheets in the paper feed direction (hereinafter, referred to as “leading ends”) from moving in the direction of insertion of the cassette. Then, when the shutter member is moved upward to the upper retracted portion from the lower restricting position in a state in which the shutter member is in abutment with the leading ends of the respective printing sheets, the lower end portion of the shutter member is rotated toward the upstream side in the paper feed direction. Accordingly, as the leading ends of the respective printing sheets in a state of being abutted with the shutter member come to an upper side in the stacking direction, the printing sheets can be aligned in sequence in the inclined state positioned on the downstream side in the paper feed direction.
However, in JP-A-2000-335769, since the shutter member is slid to the retracted position while being rotated, there is a need of a space for providing a rotating mechanism and a sliding mechanism for causing the shutter member to perform these actions. There is also a need of a space for storing the shutter member, the rotating mechanism, and the sliding mechanism to the retracted positions. Therefore, the printer is upsized due to these needed spaces.
Accordingly, a structure having a restricting surface for restricting the movement of the printing sheets toward the front in the direction of insertion of the cassette and a restricting member configured to be rotated so as to fall down in the direction of insertion is proposed. In other words, in this case, the movement of the printing sheets is restricted by the restricting surface to restrain the momentum, and then the restricting surface falls downward by the rotating action with a predetermined time lag and hence is retracted from the separating bevel, whereby the restriction of the movement of the printing sheets is released. Therefore, the printing sheets are guided to the printing unit by being separated one by one without climbing over the separating bevel. Accordingly, what is needed is just increase in space by an amount corresponding to a mechanism required for a rotating action of the restricting member without a need of a large space for storing the shutter member, the rotating mechanism, and the sliding mechanism in the retracted position, so that upsizing of the printer can be restrained.
Incidentally, a damper unit is employed in order to generate a predetermined time lag after the restriction of the printing sheets in the rotating action of the restricting member. In other words, in a first member and a second member which move (slide) relatively with respect to each other in association with the rotating action from a state in which the restricting member restricts the movement of the printing sheets to a state of releasing the restriction, the predetermined time lag is generated in the rotating action of the restricting member by the damper unit between the sliding surfaces facing when these two members slide with the intermediary of a viscous member. Therefore, generation of a desired time lag is achieved by the stable action of the damper unit.
In order to do so, sliding movement with the intermediary of the viscous member having always a constant thickness between the first member and the second member is required. In other words, parallel sliding movement of the first member and the second member without changing a gap therebetween is required. Otherwise, for example, when the second member slides while being twisted with respect to the first member, the gap between the abutting surfaces of the first member and the second member changes, and hence a damper force may vary.
Therefore, upsizing of the printer is restrained, that is, the damper unit is restrained from being upsized, and a damper unit which is reduced in variations of the damper force has been desired.